SCOPE Objectives - GI

peptic ulcer disease

characterized by discontinuation in the inner lining of the GI tract due to gastric acid secretion/pepsin

common symptoms of PUD

• epigastric abdominal pain

• bloating

• abdominal fullness

• N/V

• wt loss/gain

• hematemesis

• melena

describe the MOA for PPIs

block the gastric H, K-ATPase to inhibit gastric acid secretion

PPI agents

• omeprazole (Prilosec)

• esomeprazole (Nexium)

• lansoprasole (Prevacid)

• rabeprazole (AcipHex / Rx only)

• pantoprazole (Protonix / Rx only)

• dexlansoprazole (Dexilant / Rx only)

list ADRs of PPIs

• headache

• diarrhea

• constipation

• nausea

• itching

what CYPS metabolize PPIs

2C19 and 3A4

describe the MOA of H2 antagonists

bind to H2 receptors on the basolateral surface of gastric parietal cells (less potent than PPIs)

H2 antagonist agents

• cimetidine (Tagamet)

• famotidine (Pepcid)

• nizatidine (similar to Zantac)

list ADRs for H2 antagonists

• diarrhea

• constipation

• fatigue

• drowsiness

• headache

• muscle ache

what CYPs do cimetidine inhibit

1A2, 2C9, and 2D6

describe the MOA of bismuth subsalicylate

bactericidal and antimicrobial activity to prevent bacteria from binding and growing on the mucosal cells of the stomach

list ADRs of bismuth subsalicylate

• nausea

• bitter taste

• diarrhea

• dark/black stools

describe MOA of misoprostol (Cytotec)

synthetic prostaglandin E1 methyl ester analog that reduces gastric acid secretion

list the ADRs for misoprostol

• diarrhea

• abdominal pain

• headache

• nausea

describe the MOA of amoxicillin

bind penicillin-binding proteins that inhibit transpeptidation → lyses cell wall

list ADRs for amoxicillin

N/V/D

describe the MOA of clarithromycin

inhibits bacterial protein synthesis by binding to 50S ribosomal unit

list ADRs for clarithromycin

• N/V

• abdominal pain

• QT prolongation

• altered taste

what CYPs are inhibited by clarithromycin

3A4 and Pgp

describe the MOA of metronidazole

inhibits protein synthesis by interacting with DNA and causing cytotoxicity

list ADRs for metronidazole

• confusion

• peripheral neuropathy

• metallic taste

• N/V/D

• headache

• vaginitis

describe the MOA of tetracycline

protein synthesis inhibitor

list the ADRs of tetracycline

• N/V

• epigastric pain

• abdominal discomfort

describe the MOA of levofloxacin

directly inhibits bacterial DNA synthesis by promoting the breakage of DNA-gyrase

list the ADRs of levofloxacin

• N/D

• tendinitis

• tendon rupture

• QT prolongation

• hepatotoxicity

• photosensitivity

what CYPs do levofloxacin inhibit

2C9

semaglutide (Wegovy) dosing and patient preference

once weekly injections

prioritize patients with T2DM

liraglutide (Saxenda) dosing and patient preference

daily oral dosing

prioritize patients with T2DM (associated with increased risk of pancreatitis)

phentermine-topiramate ER (Qsymia) dosing and patient preference

daily oral dosing

preferred in patients with comorbid migraines; avoid in patients with CVD and uncontrolled HTN

naltrexone-buproprion ER (Contrave) dosing and patient preference

BID oral dosing

preferred in patients with depression or trying to quit smoking; DO NOT use with opiates or patients with seizures

treatment options for actively bleeding esophageal ulcer or visible vessel

cauterize with endoscopic therapy → high dose PPI therapy

treatment options for actively bleeding esophageal ulcer with adherent clot

no recommendation for or against cauterization → high dose PPI

treatment options for actively bleeding esophageal ulcer with flat pigmented spot

no endoscope necessary → standard PPI therapy

treatment options for actively bleeding esophageal ulcer with clean base

no endoscope necessary → standard PPI therapy

bismuth quad therapy

• bismuth QID

• PPI BID

• tetracycline (not doxy) QID

• flagyl QID

for 14 days

rifabutin triple therapy

• rifabutin

• omeprazole

• amoxicillin

all 4 capsules TID for 14 days

PCAB dual therapy

• vonoprazan BID

• amoxicillin TID

for 14 days

PCAB-clarithromycin triple therapy

• vonoprazan BID

• clarithromycin BID

• amoxicillin BID

for 14 days

prophylaxis for NSAID-induced ulcers

use COX-2 selective (celecoxib) and cotherapy with PPI, H2 antagonist or misoprostol

treatment for NSAID-induced ulcer

• if NSAID stopped: PPI or H2 antagonist for 8 wks min

• if NSAID continued: hold NSAID for tx and PPI BID, then once resolved continue PPI QD